Technical Booklet E Fire Safety·Page 107·4.20
Junctions of compartment walls and compartment floors with other walls
Junctions between compartment walls or floors and other walls must maintain the required fire resistance rating for the full period specified for the compartment wall or floor.
Where a compartment wall or compartment floor meets a compartment wall or an external wall the junction should maintain the fire resistance for a period of not less than the period of fire resistance required by the compartment wall or compartment floor.
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